/*!
* Chart.js
* http://chartjs.org/
*
* Copyright 2013 Nick Downie
* Released under the MIT license
* https://github.com/nnnick/Chart.js/blob/master/LICENSE.md
*/

//Define the global Chart Variable as a class.
window.Chart = function(context) {

	var chart = this;

	//Easing functions adapted from Robert Penner's easing equations
	//http://www.robertpenner.com/easing/

	var animationOptions = {
		linear : function(t) {
			return t;
		},
		easeInQuad : function(t) {
			return t * t;
		},
		easeOutQuad : function(t) {
			return -1 * t * (t - 2);
		},
		easeInOutQuad : function(t) {
			if ((t /= 1 / 2) < 1)
				return 1 / 2 * t * t;
			return -1 / 2 * ((--t) * (t - 2) - 1);
		},
		easeInCubic : function(t) {
			return t * t * t;
		},
		easeOutCubic : function(t) {
			return 1 * (( t = t / 1 - 1) * t * t + 1);
		},
		easeInOutCubic : function(t) {
			if ((t /= 1 / 2) < 1)
				return 1 / 2 * t * t * t;
			return 1 / 2 * ((t -= 2) * t * t + 2);
		},
		easeInQuart : function(t) {
			return t * t * t * t;
		},
		easeOutQuart : function(t) {
			return -1 * (( t = t / 1 - 1) * t * t * t - 1);
		},
		easeInOutQuart : function(t) {
			if ((t /= 1 / 2) < 1)
				return 1 / 2 * t * t * t * t;
			return -1 / 2 * ((t -= 2) * t * t * t - 2);
		},
		easeInQuint : function(t) {
			return 1 * (t /= 1) * t * t * t * t;
		},
		easeOutQuint : function(t) {
			return 1 * (( t = t / 1 - 1) * t * t * t * t + 1);
		},
		easeInOutQuint : function(t) {
			if ((t /= 1 / 2) < 1)
				return 1 / 2 * t * t * t * t * t;
			return 1 / 2 * ((t -= 2) * t * t * t * t + 2);
		},
		easeInSine : function(t) {
			return -1 * Math.cos(t / 1 * (Math.PI / 2)) + 1;
		},
		easeOutSine : function(t) {
			return 1 * Math.sin(t / 1 * (Math.PI / 2));
		},
		easeInOutSine : function(t) {
			return -1 / 2 * (Math.cos(Math.PI * t / 1) - 1);
		},
		easeInExpo : function(t) {
			return (t == 0) ? 1 : 1 * Math.pow(2, 10 * (t / 1 - 1));
		},
		easeOutExpo : function(t) {
			return (t == 1) ? 1 : 1 * (-Math.pow(2, -10 * t / 1) + 1);
		},
		easeInOutExpo : function(t) {
			if (t == 0)
				return 0;
			if (t == 1)
				return 1;
			if ((t /= 1 / 2) < 1)
				return 1 / 2 * Math.pow(2, 10 * (t - 1));
			return 1 / 2 * (-Math.pow(2, -10 * --t) + 2);
		},
		easeInCirc : function(t) {
			if (t >= 1)
				return t;
			return -1 * (Math.sqrt(1 - (t /= 1) * t) - 1);
		},
		easeOutCirc : function(t) {
			return 1 * Math.sqrt(1 - ( t = t / 1 - 1) * t);
		},
		easeInOutCirc : function(t) {
			if ((t /= 1 / 2) < 1)
				return -1 / 2 * (Math.sqrt(1 - t * t) - 1);
			return 1 / 2 * (Math.sqrt(1 - (t -= 2) * t) + 1);
		},
		easeInElastic : function(t) {
			var s = 1.70158;
			var p = 0;
			var a = 1;
			if (t == 0)
				return 0;
			if ((t /= 1) == 1)
				return 1;
			if (!p)
				p = 1 * .3;
			if (a < Math.abs(1)) {
				a = 1;
				var s = p / 4;
			} else
				var s = p / (2 * Math.PI) * Math.asin(1 / a);
			return -(a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * 1 - s) * (2 * Math.PI) / p));
		},
		easeOutElastic : function(t) {
			var s = 1.70158;
			var p = 0;
			var a = 1;
			if (t == 0)
				return 0;
			if ((t /= 1) == 1)
				return 1;
			if (!p)
				p = 1 * .3;
			if (a < Math.abs(1)) {
				a = 1;
				var s = p / 4;
			} else
				var s = p / (2 * Math.PI) * Math.asin(1 / a);
			return a * Math.pow(2, -10 * t) * Math.sin((t * 1 - s) * (2 * Math.PI) / p) + 1;
		},
		easeInOutElastic : function(t) {
			var s = 1.70158;
			var p = 0;
			var a = 1;
			if (t == 0)
				return 0;
			if ((t /= 1 / 2) == 2)
				return 1;
			if (!p)
				p = 1 * (.3 * 1.5);
			if (a < Math.abs(1)) {
				a = 1;
				var s = p / 4;
			} else
				var s = p / (2 * Math.PI) * Math.asin(1 / a);
			if (t < 1)
				return -.5 * (a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * 1 - s) * (2 * Math.PI) / p));
			return a * Math.pow(2, -10 * (t -= 1)) * Math.sin((t * 1 - s) * (2 * Math.PI) / p) * .5 + 1;
		},
		easeInBack : function(t) {
			var s = 1.70158;
			return 1 * (t /= 1) * t * ((s + 1) * t - s);
		},
		easeOutBack : function(t) {
			var s = 1.70158;
			return 1 * (( t = t / 1 - 1) * t * ((s + 1) * t + s) + 1);
		},
		easeInOutBack : function(t) {
			var s = 1.70158;
			if ((t /= 1 / 2) < 1)
				return 1 / 2 * (t * t * (((s *= (1.525)) + 1) * t - s));
			return 1 / 2 * ((t -= 2) * t * (((s *= (1.525)) + 1) * t + s) + 2);
		},
		easeInBounce : function(t) {
			return 1 - animationOptions.easeOutBounce(1 - t);
		},
		easeOutBounce : function(t) {
			if ((t /= 1) < (1 / 2.75)) {
				return 1 * (7.5625 * t * t);
			} else if (t < (2 / 2.75)) {
				return 1 * (7.5625 * (t -= (1.5 / 2.75)) * t + .75);
			} else if (t < (2.5 / 2.75)) {
				return 1 * (7.5625 * (t -= (2.25 / 2.75)) * t + .9375);
			} else {
				return 1 * (7.5625 * (t -= (2.625 / 2.75)) * t + .984375);
			}
		},
		easeInOutBounce : function(t) {
			if (t < 1 / 2)
				return animationOptions.easeInBounce(t * 2) * .5;
			return animationOptions.easeOutBounce(t * 2 - 1) * .5 + 1 * .5;
		}
	};

	//Variables global to the chart
	var width = context.canvas.width;
	var height = context.canvas.height;

	//High pixel density displays - multiply the size of the canvas height/width by the device pixel ratio, then scale.
	if (window.devicePixelRatio) {
		context.canvas.style.width = width + "px";
		context.canvas.style.height = height + "px";
		context.canvas.height = height * window.devicePixelRatio;
		context.canvas.width = width * window.devicePixelRatio;
		context.scale(window.devicePixelRatio, window.devicePixelRatio);
	}

	this.PolarArea = function(data, options) {

		chart.PolarArea.defaults = {
			scaleOverlay : true,
			scaleOverride : false,
			scaleSteps : null,
			scaleStepWidth : null,
			scaleStartValue : null,
			scaleShowLine : true,
			scaleLineColor : "rgba(0,0,0,.1)",
			scaleLineWidth : 1,
			scaleShowLabels : true,
			scaleLabel : "<%=value%>",
			scaleFontFamily : "'Arial'",
			scaleFontSize : 12,
			scaleFontStyle : "normal",
			scaleFontColor : "#666",
			scaleShowLabelBackdrop : true,
			scaleBackdropColor : "rgba(255,255,255,0.75)",
			scaleBackdropPaddingY : 2,
			scaleBackdropPaddingX : 2,
			segmentShowStroke : true,
			segmentStrokeColor : "#fff",
			segmentStrokeWidth : 2,
			animation : false,
			animationSteps : 100,
			animationEasing : "easeOutBounce",
			animateRotate : true,
			animateScale : false,
			onAnimationComplete : null
		};

		var config = (options) ? mergeChartConfig(chart.PolarArea.defaults, options) : chart.PolarArea.defaults;

		return new PolarArea(data, config, context);
	};

	this.Radar = function(data, options) {

		chart.Radar.defaults = {
			scaleOverlay : false,
			scaleOverride : false,
			scaleSteps : null,
			scaleStepWidth : null,
			scaleStartValue : null,
			scaleShowLine : true,
			scaleLineColor : "rgba(0,0,0,.1)",
			scaleLineWidth : 1,
			scaleShowLabels : false,
			scaleLabel : "<%=value%>",
			scaleFontFamily : "'Arial'",
			scaleFontSize : 12,
			scaleFontStyle : "normal",
			scaleFontColor : "#666",
			scaleShowLabelBackdrop : true,
			scaleBackdropColor : "rgba(255,255,255,0.75)",
			scaleBackdropPaddingY : 2,
			scaleBackdropPaddingX : 2,
			angleShowLineOut : true,
			angleLineColor : "rgba(0,0,0,.1)",
			angleLineWidth : 1,
			pointLabelFontFamily : "'Arial'",
			pointLabelFontStyle : "normal",
			pointLabelFontSize : 12,
			pointLabelFontColor : "#666",
			pointDot : true,
			pointDotRadius : 3,
			pointDotStrokeWidth : 1,
			datasetStroke : true,
			datasetStrokeWidth : 2,
			datasetFill : true,
			animation : false,
			animationSteps : 60,
			animationEasing : "easeOutQuart",
			onAnimationComplete : null
		};

		var config = (options) ? mergeChartConfig(chart.Radar.defaults, options) : chart.Radar.defaults;

		return new Radar(data, config, context);
	};

	this.Pie = function(data, options) {
		chart.Pie.defaults = {
			segmentShowStroke : true,
			segmentStrokeColor : "#fff",
			segmentStrokeWidth : 2,
			animation : false,
			animationSteps : 100,
			animationEasing : "easeOutBounce",
			animateRotate : true,
			animateScale : false,
			onAnimationComplete : null
		};

		var config = (options) ? mergeChartConfig(chart.Pie.defaults, options) : chart.Pie.defaults;

		return new Pie(data, config, context);
	};

	this.Doughnut = function(data, options) {

		chart.Doughnut.defaults = {
			segmentShowStroke : true,
			segmentStrokeColor : "#fff",
			segmentStrokeWidth : 2,
			percentageInnerCutout : 50,
			animation : false,
			animationSteps : 100,
			animationEasing : "easeOutBounce",
			animateRotate : true,
			animateScale : false,
			onAnimationComplete : null
		};

		var config = (options) ? mergeChartConfig(chart.Doughnut.defaults, options) : chart.Doughnut.defaults;

		return new Doughnut(data, config, context);

	};

	this.Line = function(data, options) {

		chart.Line.defaults = {
			scaleOverlay : false,
			scaleOverride : false,
			scaleSteps : null,
			scaleStepWidth : null,
			scaleStartValue : null,
			scaleLineColor : "rgba(0,0,0,.1)",
			scaleLineWidth : 1,
			scaleShowLabels : true,
			scaleLabel : "<%=value%>",
			scaleFontFamily : "'Arial'",
			scaleFontSize : 12,
			scaleFontStyle : "normal",
			scaleFontColor : "#666",
			scaleShowGridLines : true,
			scaleGridLineColor : "rgba(0,0,0,.05)",
			scaleGridLineWidth : 1,
			bezierCurve : true,
			pointDot : true,
			pointDotRadius : 4,
			pointDotStrokeWidth : 2,
			datasetStroke : true,
			datasetStrokeWidth : 2,
			datasetFill : true,
			animation : false,
			animationSteps : 60,
			animationEasing : "easeOutQuart",
			onAnimationComplete : null
		};
		var config = (options) ? mergeChartConfig(chart.Line.defaults, options) : chart.Line.defaults;

		return new Line(data, config, context);
	}

	this.Bar = function(data, options) {
		chart.Bar.defaults = {
			scaleOverlay : false,
			scaleOverride : false,
			scaleSteps : null,
			scaleStepWidth : null,
			scaleStartValue : null,
			scaleLineColor : "rgba(0,0,0,.1)",
			scaleLineWidth : 1,
			scaleShowLabels : true,
			scaleLabel : "<%=value%>",
			scaleFontFamily : "'Arial'",
			scaleFontSize : 12,
			scaleFontStyle : "normal",
			scaleFontColor : "#666",
			scaleShowGridLines : true,
			scaleGridLineColor : "rgba(0,0,0,.05)",
			scaleGridLineWidth : 1,
			barShowStroke : true,
			barStrokeWidth : 2,
			barValueSpacing : 5,
			barDatasetSpacing : 1,
			animation : false,
			animationSteps : 60,
			animationEasing : "easeOutQuart",
			onAnimationComplete : null
		};
		var config = (options) ? mergeChartConfig(chart.Bar.defaults, options) : chart.Bar.defaults;

		return new Bar(data, config, context);
	}
	var clear = function(c) {
		c.clearRect(0, 0, width, height);
	};

	var PolarArea = function(data, config, ctx) {
		var maxSize, scaleHop, calculatedScale, labelHeight, scaleHeight, valueBounds, labelTemplateString;

		calculateDrawingSizes();

		valueBounds = getValueBounds();

		labelTemplateString = (config.scaleShowLabels) ? config.scaleLabel : null;

		//Check and set the scale
		if (!config.scaleOverride) {

			calculatedScale = calculateScale(scaleHeight, valueBounds.maxSteps, valueBounds.minSteps, valueBounds.maxValue, valueBounds.minValue, labelTemplateString);
		} else {
			calculatedScale = {
				steps : config.scaleSteps,
				stepValue : config.scaleStepWidth,
				graphMin : config.scaleStartValue,
				labels : []
			}
			populateLabels(labelTemplateString, calculatedScale.labels, calculatedScale.steps, config.scaleStartValue, config.scaleStepWidth);
		}

		scaleHop = maxSize / (calculatedScale.steps);

		//Wrap in an animation loop wrapper
		animationLoop(config, drawScale, drawAllSegments, ctx);

		function calculateDrawingSizes() {
			maxSize = (Min([width, height]) / 2);
			//Remove whatever is larger - the font size or line width.

			maxSize -= Max([config.scaleFontSize * 0.5, config.scaleLineWidth * 0.5]);

			labelHeight = config.scaleFontSize * 2;
			//If we're drawing the backdrop - add the Y padding to the label height and remove from drawing region.
			if (config.scaleShowLabelBackdrop) {
				labelHeight += (2 * config.scaleBackdropPaddingY);
				maxSize -= config.scaleBackdropPaddingY * 1.5;
			}

			scaleHeight = maxSize;
			//If the label height is less than 5, set it to 5 so we don't have lines on top of each other.
			labelHeight = Default(labelHeight, 5);
		}

		function drawScale() {
			for (var i = 0; i < calculatedScale.steps; i++) {
				//If the line object is there
				if (config.scaleShowLine) {
					ctx.beginPath();
					ctx.arc(width / 2, height / 2, scaleHop * (i + 1), 0, (Math.PI * 2), true);
					ctx.strokeStyle = config.scaleLineColor;
					ctx.lineWidth = config.scaleLineWidth;
					ctx.stroke();
				}

				if (config.scaleShowLabels) {
					ctx.textAlign = "center";
					ctx.font = config.scaleFontStyle + " " + config.scaleFontSize + "px " + config.scaleFontFamily;
					var label = calculatedScale.labels[i];
					//If the backdrop object is within the font object
					if (config.scaleShowLabelBackdrop) {
						var textWidth = ctx.measureText(label).width;
						ctx.fillStyle = config.scaleBackdropColor;
						ctx.beginPath();
						ctx.rect(Math.round(width / 2 - textWidth / 2 - config.scaleBackdropPaddingX), //X
						Math.round(height / 2 - (scaleHop * (i + 1)) - config.scaleFontSize * 0.5 - config.scaleBackdropPaddingY), //Y
						Math.round(textWidth + (config.scaleBackdropPaddingX * 2)), //Width
						Math.round(config.scaleFontSize + (config.scaleBackdropPaddingY * 2)) //Height
						);
						ctx.fill();
					}
					ctx.textBaseline = "middle";
					ctx.fillStyle = config.scaleFontColor;
					ctx.fillText(label, width / 2, height / 2 - (scaleHop * (i + 1)));
				}
			}
		}

		function drawAllSegments(animationDecimal) {
			var startAngle = -Math.PI / 2, angleStep = (Math.PI * 2) / data.length, scaleAnimation = 1, rotateAnimation = 1;
			if (config.animation) {
				if (config.animateScale) {
					scaleAnimation = animationDecimal;
				}
				if (config.animateRotate) {
					rotateAnimation = animationDecimal;
				}
			}

			for (var i = 0; i < data.length; i++) {

				ctx.beginPath();
				ctx.arc(width / 2, height / 2, scaleAnimation * calculateOffset(data[i].value, calculatedScale, scaleHop), startAngle, startAngle + rotateAnimation * angleStep, false);
				ctx.lineTo(width / 2, height / 2);
				ctx.closePath();
				ctx.fillStyle = data[i].color;
				ctx.fill();

				if (config.segmentShowStroke) {
					ctx.strokeStyle = config.segmentStrokeColor;
					ctx.lineWidth = config.segmentStrokeWidth;
					ctx.stroke();
				}
				startAngle += rotateAnimation * angleStep;
			}
		}

		function getValueBounds() {
			var upperValue = Number.MIN_VALUE;
			var lowerValue = Number.MAX_VALUE;
			for (var i = 0; i < data.length; i++) {
				if (data[i].value > upperValue) {
					upperValue = data[i].value;
				}
				if (data[i].value < lowerValue) {
					lowerValue = data[i].value;
				}
			};

			var maxSteps = Math.floor((scaleHeight / (labelHeight * 0.66)));
			var minSteps = Math.floor((scaleHeight / labelHeight * 0.5));

			return {
				maxValue : upperValue,
				minValue : lowerValue,
				maxSteps : maxSteps,
				minSteps : minSteps
			};

		}

	}
	var Radar = function(data, config, ctx) {
		var maxSize, scaleHop, calculatedScale, labelHeight, scaleHeight, valueBounds, labelTemplateString;

		//If no labels are defined set to an empty array, so referencing length for looping doesn't blow up.
		if (!data.labels)
			data.labels = [];

		calculateDrawingSizes();

		var valueBounds = getValueBounds();

		labelTemplateString = (config.scaleShowLabels) ? config.scaleLabel : null;

		//Check and set the scale
		if (!config.scaleOverride) {

			calculatedScale = calculateScale(scaleHeight, valueBounds.maxSteps, valueBounds.minSteps, valueBounds.maxValue, valueBounds.minValue, labelTemplateString);
		} else {
			calculatedScale = {
				steps : config.scaleSteps,
				stepValue : config.scaleStepWidth,
				graphMin : config.scaleStartValue,
				labels : []
			}
			populateLabels(labelTemplateString, calculatedScale.labels, calculatedScale.steps, config.scaleStartValue, config.scaleStepWidth);
		}

		scaleHop = maxSize / (calculatedScale.steps);

		animationLoop(config, drawScale, drawAllDataPoints, ctx);

		//Radar specific functions.
		function drawAllDataPoints(animationDecimal) {
			var rotationDegree = (2 * Math.PI) / data.datasets[0].data.length;

			ctx.save();
			//translate to the centre of the canvas.
			ctx.translate(width / 2, height / 2);

			//We accept multiple data sets for radar charts, so show loop through each set
			for (var i = 0; i < data.datasets.length; i++) {
				ctx.beginPath();

				ctx.moveTo(0, animationDecimal * (-1 * calculateOffset(data.datasets[i].data[0], calculatedScale, scaleHop)));
				for (var j = 1; j < data.datasets[i].data.length; j++) {
					ctx.rotate(rotationDegree);
					ctx.lineTo(0, animationDecimal * (-1 * calculateOffset(data.datasets[i].data[j], calculatedScale, scaleHop)));

				}
				ctx.closePath();

				ctx.fillStyle = data.datasets[i].fillColor;
				ctx.strokeStyle = data.datasets[i].strokeColor;
				ctx.lineWidth = config.datasetStrokeWidth;
				ctx.fill();
				ctx.stroke();

				if (config.pointDot) {
					ctx.fillStyle = data.datasets[i].pointColor;
					ctx.strokeStyle = data.datasets[i].pointStrokeColor;
					ctx.lineWidth = config.pointDotStrokeWidth;
					for (var k = 0; k < data.datasets[i].data.length; k++) {
						ctx.rotate(rotationDegree);
						ctx.beginPath();
						ctx.arc(0, animationDecimal * (-1 * calculateOffset(data.datasets[i].data[k], calculatedScale, scaleHop)), config.pointDotRadius, 2 * Math.PI, false);
						ctx.fill();
						ctx.stroke();
					}

				}
				ctx.rotate(rotationDegree);

			}
			ctx.restore();

		}

		function drawScale() {
			var rotationDegree = (2 * Math.PI) / data.datasets[0].data.length;
			ctx.save();
			ctx.translate(width / 2, height / 2);

			if (config.angleShowLineOut) {
				ctx.strokeStyle = config.angleLineColor;
				ctx.lineWidth = config.angleLineWidth;
				for (var h = 0; h < data.datasets[0].data.length; h++) {

					ctx.rotate(rotationDegree);
					ctx.beginPath();
					ctx.moveTo(0, 0);
					ctx.lineTo(0, -maxSize);
					ctx.stroke();
				}
			}

			for (var i = 0; i < calculatedScale.steps; i++) {
				ctx.beginPath();

				if (config.scaleShowLine) {
					ctx.strokeStyle = config.scaleLineColor;
					ctx.lineWidth = config.scaleLineWidth;
					ctx.moveTo(0, -scaleHop * (i + 1));
					for (var j = 0; j < data.datasets[0].data.length; j++) {
						ctx.rotate(rotationDegree);
						ctx.lineTo(0, -scaleHop * (i + 1));
					}
					ctx.closePath();
					ctx.stroke();

				}

				if (config.scaleShowLabels) {
					ctx.textAlign = 'center';
					ctx.font = config.scaleFontStyle + " " + config.scaleFontSize + "px " + config.scaleFontFamily;
					ctx.textBaseline = "middle";

					if (config.scaleShowLabelBackdrop) {
						var textWidth = ctx.measureText(calculatedScale.labels[i]).width;
						ctx.fillStyle = config.scaleBackdropColor;
						ctx.beginPath();
						ctx.rect(Math.round(-textWidth / 2 - config.scaleBackdropPaddingX), //X
						Math.round((-scaleHop * (i + 1)) - config.scaleFontSize * 0.5 - config.scaleBackdropPaddingY), //Y
						Math.round(textWidth + (config.scaleBackdropPaddingX * 2)), //Width
						Math.round(config.scaleFontSize + (config.scaleBackdropPaddingY * 2)) //Height
						);
						ctx.fill();
					}
					ctx.fillStyle = config.scaleFontColor;
					ctx.fillText(calculatedScale.labels[i], 0, -scaleHop * (i + 1));
				}

			}
			for (var k = 0; k < data.labels.length; k++) {
				ctx.font = config.pointLabelFontStyle + " " + config.pointLabelFontSize + "px " + config.pointLabelFontFamily;
				ctx.fillStyle = config.pointLabelFontColor;
				var opposite = Math.sin(rotationDegree * k) * (maxSize + config.pointLabelFontSize);
				var adjacent = Math.cos(rotationDegree * k) * (maxSize + config.pointLabelFontSize);

				if (rotationDegree * k == Math.PI || rotationDegree * k == 0) {
					ctx.textAlign = "center";
				} else if (rotationDegree * k > Math.PI) {
					ctx.textAlign = "right";
				} else {
					ctx.textAlign = "left";
				}

				ctx.textBaseline = "middle";

				ctx.fillText(data.labels[k], opposite, -adjacent);

			}
			ctx.restore();
		};
		function calculateDrawingSizes() {
			maxSize = (Min([width, height]) / 2);

			labelHeight = config.scaleFontSize * 2;

			var labelLength = 0;
			for (var i = 0; i < data.labels.length; i++) {
				ctx.font = config.pointLabelFontStyle + " " + config.pointLabelFontSize + "px " + config.pointLabelFontFamily;
				var textMeasurement = ctx.measureText(data.labels[i]).width;
				if (textMeasurement > labelLength)
					labelLength = textMeasurement;
			}

			//Figure out whats the largest - the height of the text or the width of what's there, and minus it from the maximum usable size.
			maxSize -= Max([labelLength, ((config.pointLabelFontSize / 2) * 1.5)]);

			maxSize -= config.pointLabelFontSize;
			maxSize = CapValue(maxSize, null, 0);
			scaleHeight = maxSize;
			//If the label height is less than 5, set it to 5 so we don't have lines on top of each other.
			labelHeight = Default(labelHeight, 5);
		};
		function getValueBounds() {
			var upperValue = Number.MIN_VALUE;
			var lowerValue = Number.MAX_VALUE;

			for (var i = 0; i < data.datasets.length; i++) {
				for (var j = 0; j < data.datasets[i].data.length; j++) {
					if (data.datasets[i].data[j] > upperValue) {
						upperValue = data.datasets[i].data[j]
					}
					if (data.datasets[i].data[j] < lowerValue) {
						lowerValue = data.datasets[i].data[j]
					}
				}
			}

			var maxSteps = Math.floor((scaleHeight / (labelHeight * 0.66)));
			var minSteps = Math.floor((scaleHeight / labelHeight * 0.5));

			return {
				maxValue : upperValue,
				minValue : lowerValue,
				maxSteps : maxSteps,
				minSteps : minSteps
			};

		}

	}
	var Pie = function(data, config, ctx) {
		var segmentTotal = 0;

		//In case we have a canvas that is not a square. Minus 5 pixels as padding round the edge.
		var pieRadius = Min([height / 2, width / 2]) - 5;

		for (var i = 0; i < data.length; i++) {
			segmentTotal += data[i].value;
		}

		animationLoop(config, null, drawPieSegments, ctx);

		function drawPieSegments(animationDecimal) {
			var cumulativeAngle = -Math.PI / 2, scaleAnimation = 1, rotateAnimation = 1;
			if (config.animation) {
				if (config.animateScale) {
					scaleAnimation = animationDecimal;
				}
				if (config.animateRotate) {
					rotateAnimation = animationDecimal;
				}
			}
			for (var i = 0; i < data.length; i++) {
				var segmentAngle = rotateAnimation * ((data[i].value / segmentTotal) * (Math.PI * 2));
				ctx.beginPath();
				ctx.arc(width / 2, height / 2, scaleAnimation * pieRadius, cumulativeAngle, cumulativeAngle + segmentAngle);
				ctx.lineTo(width / 2, height / 2);
				ctx.closePath();
				ctx.fillStyle = data[i].color;
				ctx.fill();

				if (config.segmentShowStroke) {
					ctx.lineWidth = config.segmentStrokeWidth;
					ctx.strokeStyle = config.segmentStrokeColor;
					ctx.stroke();
				}
				cumulativeAngle += segmentAngle;
			}
			
			// renfufei@qq.com; 计算 文字
			var startAngle = -Math.PI / 2;
			for (var i = 0; i < data.length; i++) {
				var segmentAngle = rotateAnimation * ((data[i].value / segmentTotal) * (Math.PI * 2));
				
				// 反色,还未处理
				var color = "#000000" || data[i].color;
				var text = data[i].text;
				var newAngle = startAngle + segmentAngle;
				var centerAngle = (startAngle + newAngle)/2;
				// 计算坐标点
				// (width/2, height/2 是中心点) 
				var r = pieRadius;
				var x = width/2 + Math.cos(centerAngle) * r /2;
				var y = height/2 + Math.sin(centerAngle) * r /2;
				//
				ctx.fillStyle = color;
				ctx.fillText(text,x,y);
				
				startAngle = newAngle;
				if(data.length === i+1){
				    //console.dir(ctx);
				}
			}
		}

	}
	var Doughnut = function(data, config, ctx) {
		var segmentTotal = 0;

		//In case we have a canvas that is not a square. Minus 5 pixels as padding round the edge.
		var doughnutRadius = Min([height / 2, width / 2]) - 5;

		var cutoutRadius = doughnutRadius * (config.percentageInnerCutout / 100);

		for (var i = 0; i < data.length; i++) {
			segmentTotal += data[i].value;
		}

		animationLoop(config, null, drawPieSegments, ctx);

		function drawPieSegments(animationDecimal) {
			var cumulativeAngle = -Math.PI / 2, scaleAnimation = 1, rotateAnimation = 1;
			if (config.animation) {
				if (config.animateScale) {
					scaleAnimation = animationDecimal;
				}
				if (config.animateRotate) {
					rotateAnimation = animationDecimal;
				}
			}
			for (var i = 0; i < data.length; i++) {
				var segmentAngle = rotateAnimation * ((data[i].value / segmentTotal) * (Math.PI * 2));
				ctx.beginPath();
				ctx.arc(width / 2, height / 2, scaleAnimation * doughnutRadius, cumulativeAngle, cumulativeAngle + segmentAngle, false);
				ctx.arc(width / 2, height / 2, scaleAnimation * cutoutRadius, cumulativeAngle + segmentAngle, cumulativeAngle, true);
				ctx.closePath();
				ctx.fillStyle = data[i].color;
				ctx.fill();

				if (config.segmentShowStroke) {
					ctx.lineWidth = config.segmentStrokeWidth;
					ctx.strokeStyle = config.segmentStrokeColor;
					ctx.stroke();
				}
				cumulativeAngle += segmentAngle;
			}
		}

	}
	var Line = function(data, config, ctx) {
		var maxSize, scaleHop, calculatedScale, labelHeight, scaleHeight, valueBounds, labelTemplateString, valueHop, widestXLabel, xAxisLength, yAxisPosX, xAxisPosY, rotateLabels = 0;

		calculateDrawingSizes();

		valueBounds = getValueBounds();
		//Check and set the scale
		labelTemplateString = (config.scaleShowLabels) ? config.scaleLabel : "";
		if (!config.scaleOverride) {

			calculatedScale = calculateScale(scaleHeight, valueBounds.maxSteps, valueBounds.minSteps, valueBounds.maxValue, valueBounds.minValue, labelTemplateString);
		} else {
			calculatedScale = {
				steps : config.scaleSteps,
				stepValue : config.scaleStepWidth,
				graphMin : config.scaleStartValue,
				labels : []
			}
			populateLabels(labelTemplateString, calculatedScale.labels, calculatedScale.steps, config.scaleStartValue, config.scaleStepWidth);
		}

		scaleHop = Math.floor(scaleHeight / calculatedScale.steps);
		calculateXAxisSize();
		animationLoop(config, drawScale, drawLines, ctx);

		function drawLines(animPc) {
			for (var i = 0; i < data.datasets.length; i++) {
				ctx.strokeStyle = data.datasets[i].strokeColor;
				ctx.lineWidth = config.datasetStrokeWidth;
				ctx.beginPath();
				ctx.moveTo(yAxisPosX, xAxisPosY - animPc * (calculateOffset(data.datasets[i].data[0], calculatedScale, scaleHop)))

				for (var j = 1; j < data.datasets[i].data.length; j++) {
					if (config.bezierCurve) {
						ctx.bezierCurveTo(xPos(j - 0.5), yPos(i, j - 1), xPos(j - 0.5), yPos(i, j), xPos(j), yPos(i, j));
					} else {
						ctx.lineTo(xPos(j), yPos(i, j));
					}
				}
				ctx.stroke();
				if (config.datasetFill) {
					ctx.lineTo(yAxisPosX + (valueHop * (data.datasets[i].data.length - 1)), xAxisPosY);
					ctx.lineTo(yAxisPosX, xAxisPosY);
					ctx.closePath();
					ctx.fillStyle = data.datasets[i].fillColor;
					ctx.fill();
				} else {
					ctx.closePath();
				}
				if (config.pointDot) {
					ctx.fillStyle = data.datasets[i].pointColor;
					ctx.strokeStyle = data.datasets[i].pointStrokeColor;
					ctx.lineWidth = config.pointDotStrokeWidth;
					for (var k = 0; k < data.datasets[i].data.length; k++) {
						ctx.beginPath();
						ctx.arc(yAxisPosX + (valueHop * k), xAxisPosY - animPc * (calculateOffset(data.datasets[i].data[k], calculatedScale, scaleHop)), config.pointDotRadius, 0, Math.PI * 2, true);
						ctx.fill();
						ctx.stroke();
					}
				}
			}

			function yPos(dataSet, iteration) {
				return xAxisPosY - animPc * (calculateOffset(data.datasets[dataSet].data[iteration], calculatedScale, scaleHop));
			}

			function xPos(iteration) {
				return yAxisPosX + (valueHop * iteration);
			}

		}

		function drawScale() {
			//X axis line
			ctx.lineWidth = config.scaleLineWidth;
			ctx.strokeStyle = config.scaleLineColor;
			ctx.beginPath();
			ctx.moveTo(width - widestXLabel / 2 + 5, xAxisPosY);
			ctx.lineTo(width - (widestXLabel / 2) - xAxisLength - 5, xAxisPosY);
			ctx.stroke();

			if (rotateLabels > 0) {
				ctx.save();
				ctx.textAlign = "right";
			} else {
				ctx.textAlign = "center";
			}
			ctx.fillStyle = config.scaleFontColor;
			for (var i = 0; i < data.labels.length; i++) {
				ctx.save();
				if (rotateLabels > 0) {
					ctx.translate(yAxisPosX + i * valueHop, xAxisPosY + config.scaleFontSize);
					ctx.rotate(-(rotateLabels * (Math.PI / 180)));
					ctx.fillText(data.labels[i], 0, 0);
					ctx.restore();
				} else {
					ctx.fillText(data.labels[i], yAxisPosX + i * valueHop, xAxisPosY + config.scaleFontSize + 3);
				}

				ctx.beginPath();
				ctx.moveTo(yAxisPosX + i * valueHop, xAxisPosY + 3);

				//Check i isnt 0, so we dont go over the Y axis twice.
				if (config.scaleShowGridLines && i > 0) {
					ctx.lineWidth = config.scaleGridLineWidth;
					ctx.strokeStyle = config.scaleGridLineColor;
					ctx.lineTo(yAxisPosX + i * valueHop, 5);
				} else {
					ctx.lineTo(yAxisPosX + i * valueHop, xAxisPosY + 3);
				}
				ctx.stroke();
			}

			//Y axis
			ctx.lineWidth = config.scaleLineWidth;
			ctx.strokeStyle = config.scaleLineColor;
			ctx.beginPath();
			ctx.moveTo(yAxisPosX, xAxisPosY + 5);
			ctx.lineTo(yAxisPosX, 5);
			ctx.stroke();

			ctx.textAlign = "right";
			ctx.textBaseline = "middle";
			for (var j = 0; j < calculatedScale.steps; j++) {
				ctx.beginPath();
				ctx.moveTo(yAxisPosX - 3, xAxisPosY - ((j + 1) * scaleHop));
				if (config.scaleShowGridLines) {
					ctx.lineWidth = config.scaleGridLineWidth;
					ctx.strokeStyle = config.scaleGridLineColor;
					ctx.lineTo(yAxisPosX + xAxisLength + 5, xAxisPosY - ((j + 1) * scaleHop));
				} else {
					ctx.lineTo(yAxisPosX - 0.5, xAxisPosY - ((j + 1) * scaleHop));
				}

				ctx.stroke();

				if (config.scaleShowLabels) {
					ctx.fillText(calculatedScale.labels[j], yAxisPosX - 8, xAxisPosY - ((j + 1) * scaleHop));
				}
			}

		}

		function calculateXAxisSize() {
			var longestText = 1;
			//if we are showing the labels
			if (config.scaleShowLabels) {
				ctx.font = config.scaleFontStyle + " " + config.scaleFontSize + "px " + config.scaleFontFamily;
				for (var i = 0; i < calculatedScale.labels.length; i++) {
					var measuredText = ctx.measureText(calculatedScale.labels[i]).width;
					longestText = (measuredText > longestText) ? measuredText : longestText;
				}
				//Add a little extra padding from the y axis
				longestText += 10;
			}
			xAxisLength = width - longestText - widestXLabel;
			valueHop = Math.floor(xAxisLength / (data.labels.length - 1));

			yAxisPosX = width - widestXLabel / 2 - xAxisLength;
			xAxisPosY = scaleHeight + config.scaleFontSize / 2;
		}

		function calculateDrawingSizes() {
			maxSize = height;

			//Need to check the X axis first - measure the length of each text metric, and figure out if we need to rotate by 45 degrees.
			ctx.font = config.scaleFontStyle + " " + config.scaleFontSize + "px " + config.scaleFontFamily;
			widestXLabel = 1;
			for (var i = 0; i < data.labels.length; i++) {
				var textLength = ctx.measureText(data.labels[i]).width;
				//If the text length is longer - make that equal to longest text!
				widestXLabel = (textLength > widestXLabel) ? textLength : widestXLabel;
			}
			if (width / data.labels.length < widestXLabel) {
				rotateLabels = 45;
				if (width / data.labels.length < Math.cos(rotateLabels) * widestXLabel) {
					rotateLabels = 90;
					maxSize -= widestXLabel;
				} else {
					maxSize -= Math.sin(rotateLabels) * widestXLabel;
				}
			} else {
				maxSize -= config.scaleFontSize;
			}

			//Add a little padding between the x line and the text
			maxSize -= 5;

			labelHeight = config.scaleFontSize;

			maxSize -= labelHeight;
			//Set 5 pixels greater than the font size to allow for a little padding from the X axis.

			scaleHeight = maxSize;

			//Then get the area above we can safely draw on.

		}

		function getValueBounds() {
			var upperValue = Number.MIN_VALUE;
			var lowerValue = Number.MAX_VALUE;
			for (var i = 0; i < data.datasets.length; i++) {
				for (var j = 0; j < data.datasets[i].data.length; j++) {
					if (data.datasets[i].data[j] > upperValue) {
						upperValue = data.datasets[i].data[j]
					};
					if (data.datasets[i].data[j] < lowerValue) {
						lowerValue = data.datasets[i].data[j]
					};
				}
			};

			var maxSteps = Math.floor((scaleHeight / (labelHeight * 0.66)));
			var minSteps = Math.floor((scaleHeight / labelHeight * 0.5));

			return {
				maxValue : upperValue,
				minValue : lowerValue,
				maxSteps : maxSteps,
				minSteps : minSteps
			};

		}

	}
	var Bar = function(data, config, ctx) {
		var maxSize, scaleHop, calculatedScale, labelHeight, scaleHeight, valueBounds, labelTemplateString, valueHop, widestXLabel, xAxisLength, yAxisPosX, xAxisPosY, barWidth, rotateLabels = 0;

		calculateDrawingSizes();

		valueBounds = getValueBounds();
		//Check and set the scale
		labelTemplateString = (config.scaleShowLabels) ? config.scaleLabel : "";
		if (!config.scaleOverride) {

			calculatedScale = calculateScale(scaleHeight, valueBounds.maxSteps, valueBounds.minSteps, valueBounds.maxValue, valueBounds.minValue, labelTemplateString);
		} else {
			calculatedScale = {
				steps : config.scaleSteps,
				stepValue : config.scaleStepWidth,
				graphMin : config.scaleStartValue,
				labels : []
			}
			populateLabels(labelTemplateString, calculatedScale.labels, calculatedScale.steps, config.scaleStartValue, config.scaleStepWidth);
		}

		scaleHop = Math.floor(scaleHeight / calculatedScale.steps);
		calculateXAxisSize();
		animationLoop(config, drawScale, drawBars, ctx);

		function drawBars(animPc) {
			ctx.lineWidth = config.barStrokeWidth;
			for (var i = 0; i < data.datasets.length; i++) {
				ctx.fillStyle = data.datasets[i].fillColor;
				ctx.strokeStyle = data.datasets[i].strokeColor;
				for (var j = 0; j < data.datasets[i].data.length; j++) {
					var barOffset = yAxisPosX + config.barValueSpacing + valueHop * j + barWidth * i + config.barDatasetSpacing * i + config.barStrokeWidth * i;

					ctx.beginPath();
					ctx.moveTo(barOffset, xAxisPosY);
					ctx.lineTo(barOffset, xAxisPosY - animPc * calculateOffset(data.datasets[i].data[j], calculatedScale, scaleHop) + (config.barStrokeWidth / 2));
					ctx.lineTo(barOffset + barWidth, xAxisPosY - animPc * calculateOffset(data.datasets[i].data[j], calculatedScale, scaleHop) + (config.barStrokeWidth / 2));
					ctx.lineTo(barOffset + barWidth, xAxisPosY);
					if (config.barShowStroke) {
						ctx.stroke();
					}
					ctx.closePath();
					ctx.fill();
				}
			}

		}

		function drawScale() {
			//X axis line
			ctx.lineWidth = config.scaleLineWidth;
			ctx.strokeStyle = config.scaleLineColor;
			ctx.beginPath();
			ctx.moveTo(width - widestXLabel / 2 + 5, xAxisPosY);
			ctx.lineTo(width - (widestXLabel / 2) - xAxisLength - 5, xAxisPosY);
			ctx.stroke();

			if (rotateLabels > 0) {
				ctx.save();
				ctx.textAlign = "right";
			} else {
				ctx.textAlign = "center";
			}
			ctx.fillStyle = config.scaleFontColor;
			for (var i = 0; i < data.labels.length; i++) {
				ctx.save();
				if (rotateLabels > 0) {
					ctx.translate(yAxisPosX + i * valueHop, xAxisPosY + config.scaleFontSize);
					ctx.rotate(-(rotateLabels * (Math.PI / 180)));
					ctx.fillText(data.labels[i], 0, 0);
					ctx.restore();
				} else {
					ctx.fillText(data.labels[i], yAxisPosX + i * valueHop + valueHop / 2, xAxisPosY + config.scaleFontSize + 3);
				}

				ctx.beginPath();
				ctx.moveTo(yAxisPosX + (i + 1) * valueHop, xAxisPosY + 3);

				//Check i isnt 0, so we dont go over the Y axis twice.
				ctx.lineWidth = config.scaleGridLineWidth;
				ctx.strokeStyle = config.scaleGridLineColor;
				ctx.lineTo(yAxisPosX + (i + 1) * valueHop, 5);
				ctx.stroke();
			}

			//Y axis
			ctx.lineWidth = config.scaleLineWidth;
			ctx.strokeStyle = config.scaleLineColor;
			ctx.beginPath();
			ctx.moveTo(yAxisPosX, xAxisPosY + 5);
			ctx.lineTo(yAxisPosX, 5);
			ctx.stroke();

			ctx.textAlign = "right";
			ctx.textBaseline = "middle";
			for (var j = 0; j < calculatedScale.steps; j++) {
				ctx.beginPath();
				ctx.moveTo(yAxisPosX - 3, xAxisPosY - ((j + 1) * scaleHop));
				if (config.scaleShowGridLines) {
					ctx.lineWidth = config.scaleGridLineWidth;
					ctx.strokeStyle = config.scaleGridLineColor;
					ctx.lineTo(yAxisPosX + xAxisLength + 5, xAxisPosY - ((j + 1) * scaleHop));
				} else {
					ctx.lineTo(yAxisPosX - 0.5, xAxisPosY - ((j + 1) * scaleHop));
				}

				ctx.stroke();
				if (config.scaleShowLabels) {
					ctx.fillText(calculatedScale.labels[j], yAxisPosX - 8, xAxisPosY - ((j + 1) * scaleHop));
				}
			}

		}

		function calculateXAxisSize() {
			var longestText = 1;
			//if we are showing the labels
			if (config.scaleShowLabels) {
				ctx.font = config.scaleFontStyle + " " + config.scaleFontSize + "px " + config.scaleFontFamily;
				for (var i = 0; i < calculatedScale.labels.length; i++) {
					var measuredText = ctx.measureText(calculatedScale.labels[i]).width;
					longestText = (measuredText > longestText) ? measuredText : longestText;
				}
				//Add a little extra padding from the y axis
				longestText += 10;
			}
			xAxisLength = width - longestText - widestXLabel;
			valueHop = Math.floor(xAxisLength / (data.labels.length));

			barWidth = (valueHop - config.scaleGridLineWidth * 2 - (config.barValueSpacing * 2) - (config.barDatasetSpacing * data.datasets.length - 1) - ((config.barStrokeWidth / 2) * data.datasets.length - 1)) / data.datasets.length;

			yAxisPosX = width - widestXLabel / 2 - xAxisLength;
			xAxisPosY = scaleHeight + config.scaleFontSize / 2;
		}

		function calculateDrawingSizes() {
			maxSize = height;

			//Need to check the X axis first - measure the length of each text metric, and figure out if we need to rotate by 45 degrees.
			ctx.font = config.scaleFontStyle + " " + config.scaleFontSize + "px " + config.scaleFontFamily;
			widestXLabel = 1;
			for (var i = 0; i < data.labels.length; i++) {
				var textLength = ctx.measureText(data.labels[i]).width;
				//If the text length is longer - make that equal to longest text!
				widestXLabel = (textLength > widestXLabel) ? textLength : widestXLabel;
			}
			if (width / data.labels.length < widestXLabel) {
				rotateLabels = 45;
				if (width / data.labels.length < Math.cos(rotateLabels) * widestXLabel) {
					rotateLabels = 90;
					maxSize -= widestXLabel;
				} else {
					maxSize -= Math.sin(rotateLabels) * widestXLabel;
				}
			} else {
				maxSize -= config.scaleFontSize;
			}

			//Add a little padding between the x line and the text
			maxSize -= 5;

			labelHeight = config.scaleFontSize;

			maxSize -= labelHeight;
			//Set 5 pixels greater than the font size to allow for a little padding from the X axis.

			scaleHeight = maxSize;

			//Then get the area above we can safely draw on.

		}

		function getValueBounds() {
			var upperValue = Number.MIN_VALUE;
			var lowerValue = Number.MAX_VALUE;
			for (var i = 0; i < data.datasets.length; i++) {
				for (var j = 0; j < data.datasets[i].data.length; j++) {
					if (data.datasets[i].data[j] > upperValue) {
						upperValue = data.datasets[i].data[j]
					};
					if (data.datasets[i].data[j] < lowerValue) {
						lowerValue = data.datasets[i].data[j]
					};
				}
			};

			var maxSteps = Math.floor((scaleHeight / (labelHeight * 0.66)));
			var minSteps = Math.floor((scaleHeight / labelHeight * 0.5));

			return {
				maxValue : upperValue,
				minValue : lowerValue,
				maxSteps : maxSteps,
				minSteps : minSteps
			};

		}

	}
	function calculateOffset(val, calculatedScale, scaleHop) {
		var outerValue = calculatedScale.steps * calculatedScale.stepValue;
		var adjustedValue = val - calculatedScale.graphMin;
		var scalingFactor = CapValue(adjustedValue / outerValue, 1, 0);
		return (scaleHop * calculatedScale.steps) * scalingFactor;
	}

	function animationLoop(config, drawScale, drawData, ctx) {
		var animFrameAmount = (config.animation) ? 1 / CapValue(config.animationSteps, Number.MAX_VALUE, 1) : 1, easingFunction = animationOptions[config.animationEasing], percentAnimComplete = (config.animation) ? 0 : 1;

		if ( typeof drawScale !== "function")
			drawScale = function() {
			};

		requestAnimFrame(animLoop);

		function animateFrame() {
			var easeAdjustedAnimationPercent = (config.animation) ? CapValue(easingFunction(percentAnimComplete), null, 0) : 1;
			clear(ctx);
			if (config.scaleOverlay) {
				drawData(easeAdjustedAnimationPercent);
				drawScale();
			} else {
				drawScale();
				drawData(easeAdjustedAnimationPercent);
			}
		}

		function animLoop() {
			//We need to check if the animation is incomplete (less than 1), or complete (1).
			percentAnimComplete += animFrameAmount;
			animateFrame();
			//Stop the loop continuing forever
			if (percentAnimComplete <= 1) {
				requestAnimFrame(animLoop);
			} else {
				if ( typeof config.onAnimationComplete == "function")
					config.onAnimationComplete();
			}

		}

	}

	//Declare global functions to be called within this namespace here.

	// shim layer with setTimeout fallback
	var requestAnimFrame = (function() {
		return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame ||
		function(callback) {
			window.setTimeout(callback, 1000 / 60);
		};
	})();

	function calculateScale(drawingHeight, maxSteps, minSteps, maxValue, minValue, labelTemplateString) {
		var graphMin, graphMax, graphRange, stepValue, numberOfSteps, valueRange, rangeOrderOfMagnitude, decimalNum;

		valueRange = maxValue - minValue;

		rangeOrderOfMagnitude = calculateOrderOfMagnitude(valueRange);

		graphMin = Math.floor(minValue / (1 * Math.pow(10, rangeOrderOfMagnitude))) * Math.pow(10, rangeOrderOfMagnitude);

		graphMax = Math.ceil(maxValue / (1 * Math.pow(10, rangeOrderOfMagnitude))) * Math.pow(10, rangeOrderOfMagnitude);

		graphRange = graphMax - graphMin;

		stepValue = Math.pow(10, rangeOrderOfMagnitude);

		numberOfSteps = Math.round(graphRange / stepValue);

		//Compare number of steps to the max and min for that size graph, and add in half steps if need be.
		while (numberOfSteps < minSteps || numberOfSteps > maxSteps) {
			if (numberOfSteps < minSteps) {
				stepValue /= 2;
				numberOfSteps = Math.round(graphRange / stepValue);
			} else {
				stepValue *= 2;
				numberOfSteps = Math.round(graphRange / stepValue);
			}
		};

		var labels = [];
		populateLabels(labelTemplateString, labels, numberOfSteps, graphMin, stepValue);

		return {
			steps : numberOfSteps,
			stepValue : stepValue,
			graphMin : graphMin,
			labels : labels

		}

		function calculateOrderOfMagnitude(val) {
			return Math.floor(Math.log(val) / Math.LN10);
		}

	}

	//Populate an array of all the labels by interpolating the string.
	function populateLabels(labelTemplateString, labels, numberOfSteps, graphMin, stepValue) {
		if (labelTemplateString) {
			//Fix floating point errors by setting to fixed the on the same decimal as the stepValue.
			for (var i = 1; i < numberOfSteps + 1; i++) {
				labels.push(tmpl(labelTemplateString, {
					value : (graphMin + (stepValue * i)).toFixed(getDecimalPlaces(stepValue))
				}));
			}
		}
	}

	//Max value from array
	function Max(array) {
		return Math.max.apply(Math, array);
	};
	//Min value from array
	function Min(array) {
		return Math.min.apply(Math, array);
	};
	//Default if undefined
	function Default(userDeclared, valueIfFalse) {
		if (!userDeclared) {
			return valueIfFalse;
		} else {
			return userDeclared;
		}
	};
	//Is a number function
	function isNumber(n) {
		return !isNaN(parseFloat(n)) && isFinite(n);
	}

	//Apply cap a value at a high or low number
	function CapValue(valueToCap, maxValue, minValue) {
		if (isNumber(maxValue)) {
			if (valueToCap > maxValue) {
				return maxValue;
			}
		}
		if (isNumber(minValue)) {
			if (valueToCap < minValue) {
				return minValue;
			}
		}
		return valueToCap;
	}

	function getDecimalPlaces(num) {
		var numberOfDecimalPlaces;
		if (num % 1 != 0) {
			return num.toString().split(".")[1].length
		} else {
			return 0;
		}

	}

	function mergeChartConfig(defaults, userDefined) {
		var returnObj = {};
		for (var attrname in defaults) {
			returnObj[attrname] = defaults[attrname];
		}
		for (var attrname in userDefined) {
			returnObj[attrname] = userDefined[attrname];
		}
		return returnObj;
	}

	//Javascript micro templating by John Resig - source at http://ejohn.org/blog/javascript-micro-templating/
	var cache = {};

	function tmpl(str, data) {
		// Figure out if we're getting a template, or if we need to
		// load the template - and be sure to cache the result.
		var fn = !/\W/.test(str) ? cache[str] = cache[str] || tmpl(document.getElementById(str).innerHTML) :

		// Generate a reusable function that will serve as a template
		// generator (and which will be cached).
		new Function("obj", "var p=[],print=function(){p.push.apply(p,arguments);};" +

		// Introduce the data as local variables using with(){}
		"with(obj){p.push('" +

		// Convert the template into pure JavaScript
		str.replace(/[\r\t\n]/g, " ").split("<%").join("\t").replace(/((^|%>)[^\t]*)'/g, "$1\r").replace(/\t=(.*?)%>/g, "',$1,'").split("\t").join("');").split("%>").join("p.push('").split("\r").join("\\'") + "');}return p.join('');");

		// Provide some basic currying to the user
		return data ? fn(data) : fn;
	};
}

